Yoda has plans within plans. The more he talks to Luke, the more this becomes clear. He uses his intellect far more than his feeling. He lives in his own little world, and he seemingly does not need any romantic engagements. That is trademark INTJ. Yet I am having trouble pegging him as INTJ or INFJ. He is either INTJ with a very strongly developed F and N, or an INFJ with a very strongly developed T. Anything you think that would push him more one way than the other?

Yoda has plans within plans. The more he talks to Luke, the more this becomes clear. He uses his intellect far more than his feeling. He lives in his own little world, and he seemingly does not need any romantic engagements. That is trademark INTJ. Yet I am having trouble pegging him as INTJ or INFJ. He is either INTJ with a very strongly developed F and N, or an INFJ with a very strongly developed T. Anything you think that would push him more one way than the other?

Yoda is very connected to humanity and the outside world, despite not being at all romantic. That is quite Fe. If anything, an INTJ would be significantly more romantic (due to tertiary Fi in combination with Ni), as well as colder and much more detached from his peers. An INTJ would be Palpatine; or for a non-evil example, Michael Scofield from Prison Break.

Having plans within plans is just Ni (which all NJs share). It means that he thinks far ahead.